How can I call the individual parts of the position attribute vector (X, Y, and Z) as values in geometry nodes?
Instead of Attribute Vector Math multiplying position with [1,0,0], to get the X component alone, you could take the Attribute Vector Math dot-product of position and [1,0,0]. (Likewise for Y and Z)
However, I think you'd be a lot better off using 2.93 alpha, to get into Geometry Nodes.. you can see what you're doing a lot more easily: